KDiff3 is a graphical text difference analyzer for up to 3 input files, provides character-by-character analysis and a text merge tool with integrated editor. It can also compare and merge directories. Platform-independant.

RText is a customizable programmer's text editor written in Java. Some of its features include: syntax highlighting, editing multiple documents at once, printing and print preview, find/replace/find in files dialogs, undo/redo, and online help.

gPDFText is a text editor for GTK+ that opens PDF documents for ebook readers, converts the text contents into plain ASCII text, restores the original paragraphs and removes unwanted line breaks to allow easier zooming on the reader.